Self-assembly of MAPbBr3/Pb-MOF heterostructures with enhanced photocatalytic CO2 reduction performance and stability

Abstract

The appropriate and adjustable band structure and positive visible-light response enable the halide perovskite MAPbBr₃ to be a promising photocatalyst for CO₂ reduction. Considering the extremely poor water resistance and severe carrier complexation trends, rational design and control of steam stable MAPbBr₃-based heterojunction nanocrystals to exploit their potential for photocatalytic CO₂ reduction in steam is important while being a challenging topic. Here, an efficient MAPbBr₃/Pb-MOF heterojunction photocatalyst is developed, ensuring in situ growth of Pb-MOF on the surface of the perovskite via a self-sacrificial template method, thus creating tightly connected interfaces to mitigate the sluggish charge transfer due to the discontinuous interfaces. The experimental results confirm that construction of MAPbBr₃/Pb-MOF heterojunctions suppresses the recombination of photogenerated carriers. Meanwhile, the prepared MAPbBr₃/Pb-MOF exhibits better steam stability, CO₂ adsorption capacity, and higher separation efficiency of photogenerated carriers. The heterostructure enables the photocatalytic reduction of CO₂ to CO at an excellent rate of 21.5 μmol g⁻¹ under visible light irradiation, which is 4.8 times larger than that of pristine MAPbBr₃.